We present a detailed study of several hydrogen-bonded dimers consisting of H2O, NH3, and HF molecules using the Symmetry Adapted Perturbation Theory (SAPT) at different levels of approximations. The relative importance of each individual perturbational components and the quality of the total interaction energies obtained are discussed. The dependence of the results on the relative orientation of the molecules of the dimers and on the intermonomer distance is also investigated.